The lace goanna is the second largest lizard in Australia. It is widespread in eastern Queensland, eastern New South Wales and most of Victoria but is restricted to the extreme south-east of South Australia (Houston 1978). They also inhabit some islands off the eastern coast (e.g. Mackay 1959). Lace goannas will live wherever there are trees and are common in many areas (Kreeft 1886, Richardson 1976, Jenkins & Bartell 1980). Peters (1967) found them close to the middle of Sydney. Its habitat includes rainforest as well as many drier woodlands. As would be expected of such a ubiquitous lizard, its pattern varies between areas. A vividly banded form (sometimes known as V.varius bellii) is also found in parts of Queensland and New South Wales which lives alongside those of normal pattern. The ecological implications of the pattern change are unknown (but see Grundke & Grundke 1992a). Horn's (1980) suggestion that all banded animals are males has been discounted (Greer 1989).

Varanus varius

In 1886 Krefft suggested that lace goannas grow as large as 250cm. None of this size exist now and specimens of 200cm TL are exceptional. A lizard from Mallacoota, Victoria measured 75cm SVL, 192cm TL and weighed 14kg (Weavers 1988). Another from Healesville was 198cm long and weighed almost 20.5kg. It was found to have eaten four foxcubs, three young rabbits and three large lizards (Fleay 1950). In contrast, a large male caught by Stebbins & Barwick (1968) in the spring measured 150cm TL and weighed 4.2kg. Males grow larger than females and probably have larger home ranges (Carter 1990).

The lace goanna is a superb climber, equipped with massive strongly curved claws and can move through branches with great agility. Eggs and chicks of a large number of ground and tree nesting birds have been recorded as falling prey to the lace goanna (Lucas & Dudley 1909; Carter 1924; Barrett 1928 Hindwood 1926: Gogerly 1922 Hyem 1936; Broadbent 1910; Goulburnite 1908; Kaveny 1958). They may feed on birds to a greater extent than any other monitor lizard. Outside the nesting season a variety of mammals (including kangaroos, opossums and bats), snakes, lizards, turtle eggs, crocodile eggs, fish, spiders, snails and insects as small as ants are eaten (Krefft 1886, Vestjens 1977, Kennerson 1980, Mansergh & Huxley 1985, Webb 1982; Losos & Greene 1988; Webber 1993). They will also eat carrion, even when it is in a very advanced state of decay (Kennerson 1980, Ward & Carter 1988) and will forage in human rubbish (Rose 1974). Krefft (1886) reported finding "several pounds of bones" in the stomach of one individual. Peters (1967) thought that the diet of adults was comprised largely of rodents and reptiles. Vincent (1981) suggested that lace goannas feed purposely on berries.

The lace goanna is a very active lizard that searches for food both in trees and on the ground. When threatened they will invariable take shelter in the nearest tree and try to hide on the opposite side of the trunk as their aggressor. It seems likely that many large prey are caught after a chase over the ground. Horn (1981) found that males outnumber females by 8:1, but these animals are notoriously difficult to sex without internal examination. Ritual combat occurs in the typical bipedal manner (Twigg 1988; Horn et al 1994). In southern parts of Australia activity is reduced or halted during the cooler months. They shelter in burrows or tree hollows.

Varanus bitatawa is the third species of monitor lizard to be
recognised by science that belongs to the "Pandan Biawak" group, all of
which are of at least as great a conservation concern as the Komodo
dragon, but receive virtually none of the attention. Pandan Biawak occur
only in lowland dipterocarp forest. The first species (Varanus
olivaceus or Butaan) was discovered in 1845 and not seen alive by a
scientist until the late 1970s. The next species (Varanus mabitang or
Mabitang) was discovered in 2001 and in 2010 Varanus bitatawa (Butikaw
or Bitatawa) was described. Other species of frugivorous monitor lizards
may remain undescribed, but many may have gone extinct without ever
having been recognised.